VOLUME Xra OCTOBER, 1934 number 4 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIFIC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



An Extension of the Theory of Three-Electrode Vacuum 

 Tube Circuits — S. A, Levin and Liss C. Peterson 523 



The Electromagnetic Theory of Coaxial Transmission 

 Lines and Cylindrical Shields — S. A. Schelkunoff 532 



Contemporary Advances in Physics, XXVIII — ^The 



Nucleus, Third Part— ^arZ K. Darrow .... 580 



The Measurement and Reduction of Microphonic 



Noise in Vacuum Tubes — D. B. Penick .... 614 



Fluctuation Noise in Vacuum Tubes — G. L. Pearson . 634 



Systems for Wide-Band Transmission Over Coaxial 

 Lines — L. Espenschied and M. E, Strieby . . . 654 



Regeneration Theory and Experiment — E. Peterson, 

 J. G. Kreer, and L. A. Ware 680 



Abstracts of Technical Papers . 701 



Contributors to this Issue 704 



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